Originally posted by Big G 1) It seems two seperate lenses from seperate manufacturers need the same level of adjustment, that suggests that my body is slightly out. Is +4 a front-focus or back-focus issue?
Seems likely that the body is slightly out.
With positive values you are correcting back focus. But you should see that from your test images.
You may want to look at these
AF adjustment hints.
Originally posted by Big G 2) Does the K-7 have this AF adjustment in body, or only by way of a debug menu?
The K-7 supports AF adjustment for several lenses without resorting to a debug menu.